谐振腔

Stability of double Nd: YVO4 crystals laser′s equivalent cavity is analyzed, theory result expresses that crystal′s thermal lens generated by laser crystal absorbing pumped power will play important effects to cavity stability.

对平行平面谐振腔的等效腔进行了理论分析，结果表明激光晶体吸收泵浦光产生的热透镜效应对保持腔的稳定性起到了重要的作用。

The stable region＇s boundary curve expression is obtained with the off-focus amount as a design parameter.

分析结果表明，对于子腔预先给定的参量，只要另一子腔满足适当的失调量，整个谐振腔就是稳定的。

The resonance property of the pair of left-handed metamaterial and negative permittivity medium is analyzed in depth, and the results are applied to the design of an improved miniaturized cavity resonator.

通过探讨双负介质与负介电常数介质交叠结构的谐振特性，实现了一种能够同时缩小长度和宽度的改进的小型化谐振腔。

The principle of the optical differentiator is that when the silicon-based annular cavity resonator meets or is close to a critical coupling state, the spectra characteristic of the silicon-based annular cavity resonator is quite similar to the differentiator within certain range with the resonant wavelength as the center.

本发明的原理是当硅基环形谐振腔满足或接近临界耦合状态时，其在谐振波长为中心的一定范围内的频谱特性是微分器的很好的近似。

The positions at cavity mirror of ray which propagates back and forth in the CCP laser resonator are analyzed, it shows that the CCP resonator with three equal dihedral angle errors (three dihedral angle errors are not 0) is an unstable resonator.

对在腔内往返传输的光线在镜面上的位置进行了分析，结果表明：3个二面角误差相同且不为零的角锥棱镜构成的谐振腔为约束非稳腔。

The model for calculating the stability of the resonator containing a laser rod with curvature ends was developed,which was based on the transfer matrix theory of Gauss beam. The results from the numerical simulations on some typical resonators indicate that the laser rod with curvature ends can expand the stable region of plano-plano,plano-concave and plano-convex cavity notability;despite the laser rod with curvature ends can improve the stability of above mentioned cavities,it costs the effective mode volume.

计算结果表明，对于几类典型的谐振腔如平平腔、平凹腔，球面端面激光棒可以显著的扩展强热聚焦作用下的稳定工作范围；球面端面激光棒在提高约束稳定性和热稳定性的同时，通常是以牺牲有效模式体积为代价的。

Plate and λ/2 plate were placed inside the Nd∶YVO4KTP green laser cavity with angle 90°between their fast axis.The composite plate composed of HWP,QWP and KTP has the function of QWP.The composite plate with Nd∶YVO4 can effectively suppress the coupling of polarized modes,and multi-longitudinal-mode lownoise green laser was obtained.Since the composite plate counteracted the phase shift induced by temperature sensitivity of quartz plate,the green laser operated with lownoise reliability in different output power and different operation temperature.The threelongitudinalmode, the noise of less than 0.5% and output power stability of less then 1% for 12 hour are obtained in the green laser.

介绍了一种LD泵浦腔内倍频全固体Nd∶YVO4KTP多纵模、低噪音、高功率稳定绿激光器在Nd∶YVO4KTP绿激光器组成的谐振腔内放置厚度约相等的石英晶体λ2波片和λ4波片，使两波片快轴夹角互呈90°，HWP、QWP与KTP构成复合波片，其作用相当于QWP，此复合波法与各相异性Nd∶YVO4共同作用有效抑制了腔内偏振模耦合，获得多纵模低噪音绿光输出此复合波片相互作用由于抵消了石英晶体波片温度敏感引起的相位延迟量漂移，所以此激光器在不同功率、不同工作温度下，均能稳定可靠地运转于低噪音状态实验结果为，绿光输出纵模数为3个，噪音小于0.5%，12 h功率稳定性优小于1

Experimental results show that in asymmetric flat-flat resonators, when the laser crystal′s position is varied relative to two cavity mirrors, the output power changes in different way, and the radially polarized and azimuthally polarized focal lengths are 31.76 m·W, 42.26 m·W measured respectively.

实验结果表明，在非对称平-平腔中，当激光晶体相对于两面腔镜位置不同时，谐振腔输出功率会出现不同的变化趋势，测量出径向热透镜系数为31.76 m·W和切向热透镜系数为42.26 m·W。

Considering the thermal-induced birefringence, the g parameter coordinate system is analyzed, the formulas of radially polarized and azimuthally polarized focal lengths in three different cavity structures are deduced and the proper cavity structure to get the thermal focal length coefficients is presented.

考虑热致双折射效应，利用等效谐振腔的g参数坐标图进行分析，推导了三种不同腔型结构下径向热透镜焦距和切向热透镜焦距系数的计算方法，分析并得出了测量热透镜焦距系数所需的腔型结构。

Grounding on the purpose of industrialization of laser, based on the thought of astigmatism compensation and thermal stability of the cavity, we employed high power LD to pump Nd:YVO4 crystal and used the introcavity frequency doubling with type 1 noncritical phase-match LBO crystal, which has high damage threshold. The cavity parameters are optimized by the use of ABCD theory and the resonatorstructure CAD software.

立足于激光器的产品化，基于谐振腔的像散补偿和热稳定性的设计思想，采用大功率LD单端泵浦Nd：YVO_4晶体，具有高光损伤阈值的Ⅰ类非临界相位匹配LBO晶体腔内倍频方案，应用ABCD定律和腔结构模拟软件CDA设计并优化了一组腔参数。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。